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Arduino FTDI Programming
The key change from the FTDI cables to our Arduino compatible boards is that we swapped pin 6 from RTS to DTR. This change was required to match Arduino’s method of resetting the ATmega328P using the DTR signal.
FTDI Pinout Arduino compatible pinout is slightly different from the FTDI cable (pin 6) Note The signal difference on pin 6 may cause these devices to not be 100% compatible with devices designed for use with the FTDI TTL-232R cables. Advantages Having a detachable USB to UART bridge comes with several advantages over boards like the Arduino Uno.
Removing the computer interface makes the board smaller. You only need to buy the circuit once and can program many Arduinos. The bridge circuitry draws power (up to 500 mW) that’s not needed in many installed applications. Removing this parasitic drain makes your project more power efficient & your batteries last longer.